In the KEYNOTE-522 study (Schmid et al. 2020), it was also found that pembrolizumab combined with chemotherapy significantly improved the pCR (Pathological Complete Response) rate of triple-negative breast cancer in PD-L1 positive patients (68.9%), while the pCR rate was 45.3% in negative patients. This evidence concerns the gene CD274 and triple-negative breast carcinoma.